Question
My 5-year-old uses a cochlear implant, has just started kindergarten, and has begun to use the personal FM system. There seems to be a difference in opinion by audiologists as to whether a separate map for the processor should be used when using the FM system. I would appreciate your opinion and explanation.
Answer
Every audiologist may have individual recommendations which may reflect his/her observations of other implant recipients using the same equipment. More specifically, he/she may have found that a certain MAP adjustment has been successful in his/her own practice, and thus applies that adjustment routinely. With Nucleus sound processors, there are some adjustments which are made more routinely, however these vary from processor to processor.
The key is to evaluate the child's speech perception without the FM system, then add the FM system to ensure that performance is equal. It is at this point that modifications to the FM receiver gain may be required. Then, one would want to evaluate the child's speech perception in noise without the FM system, followed by testing with the FM system in use to verify the amount of FM benefit obtained. If there is not significant benefit in noise, adjustments to the sound processor microphone sensitivity or Accessory Mix Ratio may allow for additional FM benefit.
The child should be able to report any problems which would require troubleshooting of the equipment, but there should also be school personnel available to listen to the system routinely to ensure that all is working properly.
For more information about cochlear implants, visit www.cochlear.com
Janet Clarke, Au.D., is a Technical Support Audiologist for Cochlear Americas, manufacturer of Nucleus Cochlear Implant Systems.